An image-capturing sensor such as a CCD is utilized in an electronic camera or the like to capture an image of a subject. At such an image-capturing sensor, color filters each corresponding to one of, for instance, three colors, R, G and B (red, green and blue) are arranged in a Bayer array, and image data containing color information corresponding to one of the color components, R, G and B are output from each pixel. In the image data a given pixel only contains color information on one color component. Accordingly, various methods for obtaining color information corresponding to color components missing at the pixel through interpolation processing or the like have been proposed.
Japanese Patent No. 2931520 discloses a technology whereby the color level of a given pixel is detected, a correlational value is adjusted in correspondence to the color level and interpolation processing is executed based upon the adjusted correlational value.
However, if the image being processed contains a structure, the value indicated by a color difference signal attributable to the structural factor cannot be distinguished from the value of the color difference signal generated due to the actual color of the image area in the color level detection method disclosed in Japanese Patent No. 2931520, and thus, there is a high risk of the correlational value being used incorrectly by mistake.